STYLE: use globalIndex localSize(), totalSize() in more places

- more explicit meaning than offset(), size() - respectively.

src/functionObjects/field/streamLine/streamLineBase.C

@@ -563,7 +563,7 @@ bool Foam::functionObjects::streamLineBase::writeToFile()
 
         const mapDistribute distMap
         (
-            globalTrackIDs.size(),
+            globalTrackIDs.totalSize(),
             std::move(sendMap),
             std::move(recvMap)
         );